Currently it's hardcoded for each board which defaultenv version is
used. This is unfortunate since some people like the other defaultenv
version better and may want to select it.

This patch removes the board specific environment path
CONFIG_DEFAULT_ENVIRONMENT_PATH and instead adds it via:

	if (IS_ENABLED(CONFIG_DEFAULT_ENVIRONMENT_GENERIC))
		defaultenv_append_directory(defaultenv_<board>);

This way we can make sure that the defaultenv-1 board specific bits are
only compiled in when defaultenv-1 is actually in use.

The next step is to make the defaultenv version selection a user visible
choice.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

This renames the Freescale and Phytec board directories and defconfig
files to a common naming scheme. The board directories are named
<vendor>-<board> and the defconfig files are named
<vendor>-<board>_defconfig. Also the DataModul realq7 is renamed to its
Marketing Name eDM-QMX6.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>